Neb. Rev. Stat. § 48-660: Neb. Rev. Stat. § 48-660

If more than the correct amounts of combined tax or interest are collected, then, under rules and regulations made under section 48-607 , proper adjustments with respect thereto shall be made, without interest, in connection with subsequent combined tax. If such adjustment cannot be made within a reasonable time, the commissioner shall refund the excess from the appropriate fund. Applications for adjustments or refunds shall be made within four years after the date of such overcollection.